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Objective: This study aimed to investigate the protective effect and underlying mechanism of a combined glutamine and curcumin formulation on ethanol-induced gastric mucosal damage in rats. Method: A total of fifty SPF-grade healthy SD male rats were randomly partitioned into five groups: A normal group, a model control group, a cimetidine group, a high-dose treatment group, and a low-dose treatment group. After a period of 30 days marked by oral gavage administration, all groups, with the exception of the normal group, were euthanized post anhydrous ethanol-induced modeling. The histopathological alterations in the gastric mucosa were observed via hematoxylin & eosin (H&E) staining. Furthermore, serum levels of malondialdehyde (MDA), nitric oxide (NO), and glutathione peroxidase (GSH-PX) were ascertained using a specific reagent kit. Concurrently, the concentration of prostaglandin E2 (PGE2) within the tissue and the expression levels of heme oxygenase-1 (HO-1), NADPH quinone oxidoreductase (NQO1), the antioxidant-related nuclear factor-E2-related factor 2 (Nrf2) gene, and glycogen synthase kinase-3β (GSK-3β) were evaluated. Results: In the cimetidine and high-dose treatment groups, the incidence of gastric mucosal bleeding and other forms of injury were noticeably mitigated (P

In this study, the flavonoids in peony seed meal were separated and purified by microfiltration-nanofiltration secondary membrane separation method. The effects of material-liquid ratio, extraction temperature, ethanol volume fraction and extraction time on the extraction amount of total flavonoids were investigated by single-factor experiments, and the extraction process was optimized and validated by response surface methodology on the basis of single factors. Eight types of microfiltration membranes, including polyvinylidene fluoride (PVDF), polyethersulfone (PES), polytetrafluoroethylene (PTFE), polypropylene (PP), mixed cellulose (MCE), polyacrylonitrile (PAN), aqueous acetate (CA) and polyamide (PA), were selected for the primary separation of PSMF extracts. The nanofiltration membranes were homemade organosilicon/PA composite membranes in the laboratory. The results showed that the optimum extraction conditions for PSMF were 1:15 g/mL, 50 ℃, 70% ethanol volume fraction, 30 min, (240.28±2.25) μg/mL of PSMF extraction amount. The PA membrane had a better separation effect, and the composite membrane had a better purification effect on PSMF, and the water solubility of flavonoids was increased to more than 90% after separation. After calcination at 800 ℃, the residual mass of the raw material solution was 1.43% and that of the PA membrane separation was 0.76%, and the BTESE/PA composite membrane was reduced to 0.26%, with fewer impurities and higher purity. Comparing its antioxidant activity before and after separation, the ·OH, DPPH· scavenging rate and reducing power were improved after separation, and the O2−· scavenging rate decreased from 79.94% to 64.82%. In this study, the active components in peony seed meal were analyzed. PSMF would be a novel phytoflavonoid resource with rich composition and certain research space.

In order to explore dynamic changes in the physicochemical characteristics and microbial diversity of modified atmosphere packaged braised chicken during refrigeration, high-throughput sequencing technology and traditional isolation and identification methods were combined to study the physical and microbial changes of modified atmosphere packaged (25% CO2/75% N2) braised chicken during storage at 4 ℃ for 10 days. The results showed that total volatile basic nitrogen (TVB-N) content and total bacterial count increased significantly during storage (P 0.05). These changes were related to the gas composition in modified atmosphere packaging. The microbial species richness of braised chicken was the highest at the early stage of storage, and then decreased gradually. At the initial stage of storage, the relative abundance of Enterobacteriaceae, Acinetobacter and Aeromonas were high. At the middle and late stages of storage, the relative abundance of Weissella and Enterobacter were high. The relative abundance of Weissella, Enterobacter, Lactococcus and Leuconostoc increased gradually during the whole storage period and their growth was dominant. Six species of spoilage organisms were isolated and identified, namely, Lactobacillus curvatus, Bacillus cereus, Bacillus safensis, Serratia liquefaciens, Hafnia sp. and Enterobacter sp., which could be the major causes of the rot of braised chicken under modified atmosphere packaging conditions.

Using hulled hemp seed powder as raw material, nitrogen was introduced to produce positive pressure cavitation, which realized the effect of accelerating the protein extraction rate. Taking the yield of protein as the evaluation index, the effects of pH, temperature, time, material-liquid ratio and aeration on protein extraction rate were explored by combining univariate test and response surface test. Results showed that, the optimal process conditions for nitrogen-assisted positive pressure cavitation extraction of hemp seed protein were as follows: The material-liquid ratio was 1:50 (g/mL), the pH was 12, the extraction temperature was 52 °C, the extraction time was 50 min, and the nitrogen ventilation was 1.6 L/min, under these conditions, the protein yield was 76.03%±1.64%. It was significantly higher than the magnetic stirring method under the same conditions by 56.32%. The physicochemical properties of hemp seed protein extracted by four methods (positive pressure alkaline solubility, magnetic alkaline solubility, positive pressure enzymatic hydrolysis, and magnetic enzymatic hydrolysis) were compared, and the results showed that the foaming and oil-holding properties of the proteins by magnetic alkalinity solution method were the strongest, 145% and 246%, respectively. There was little difference between water holding capacity and emulsification of the four methods. The protein denaturation temperature of the four extraction methods was compared, and the termination temperature of protein denaturation of the positive pressure alkaline solution method was 105.5 ℃, which was 4~13 ℃ higher than the other three methods. Hemp seed protein treated by positive pressure enzymatic hydrolysis contains 17 amino acids and an EAA/TAA score of nearly 40%, which was very in line with the FAO/WHO recommendation for high-quality protein. Experiments showed that nitrogen-assisted positive pressure cavitation could increase the extraction rate of hemp seed protein and had good physicochemical properties.

The resistance to melting is an important indicator of the quality of ice cream. During transport, storage and distribution, poorly melting resistance ice cream will inevitably become deformed due to fluctuations in ambient temperature, which in turn will affect the consumer experience, product sales and even the brand's reputation. Stabilisers are crucial to the melting resistance of ice cream. This paper reviews the mechanisms of stabilisers on ice cream melting resistance, the properties of different anionic/non-ionic stabilisers and their mechanism of actionon ice cream resistance, mainly in terms of gel formation, inhibition of ice crystal growth and enhancement of ice cream serum phase viscosity. Furtherly, it provides theoretical guidance for the development of cultural and creative ice cream, ice cream with complex structure and ice cream circulation.

To obtain high-quality walnut meal protein, the process conditions for extraction of walnut meal protein by alkaline solubilization and acid precipitation method and purification of walnut meal protein by glycolytic enzyme were optimized by single-factor experiments and response surface method, respectively, and the functional properties such as solubility, water absorption, and emulsification were analyzed. The optimal extraction process conditions were: pH12, temperature 55 ℃, time 90 min, and material-liquid ratio 1:40 g/mL. Under these conditions, the extraction rate of walnut meal protein could reach 81.89%±1.64%, and its settling point was pH4.5. The optimal purification process conditions were: pH4.5, material-to-liquid ratio 1:40 g/mL, enzymatic digestion time 129 min, enzymatic digestion temperature 53°C, and enzyme addition 0.4%. The purity of walnut meal protein purified under these conditions could reach 94.48%±1.83%. The results of functional properties of walnut protein showed that its solubility was 24.82%, water absorption 3.06 g/g, oil absorption 3.15 g/g, emulsification 16.10 m2/g, emulsification stability 38.87 min, foaming 30.53% and foaming stability 75.44% under the same pH conditions, and the purified walnut protein had better functional properties.

In this study, the culture medium of a recombinant Pichia kudriavzevii M48 overexpressed MET14 gene with high cadmium resistance and cadmium removal rate was optimized. Taking the comprehensive value of cadmium removal rate and biomass as the evaluation index, the medium composition was optimized through single factor test, 25-1 fractional factorial design and central composite design, so as to provide a research basis for making the recombinant strain M48 into cadmium removal preparation in the later stage. The results showed that the optimal medium was 23.42 g/L glucose, 27.72 g/L yeast extract and 2.04 g/L of potassium dihydrogen phosphate. Under these conditions, the cadmium removal rate of M48 was 79.63% and the biomass was 9.95 g/L, which were 2.70 and 1.16 times higher than that before optimization, respectively. Therefore, the cadmium removal rate and biomass of recombinant strain M48 were effectively increased by optimizing the medium composition.

Irritable bowel syndrome (IBS) is a common gastrointestinal disease. The main clinical symptoms are abdominal pain, bloating, abnormal defecation frequency and character. The pathogenesis of the disease is complex, including genetic factors, dietary differences, gut microbiota changes, gastrointestinal infection and brain-gut axis dysfunction. The main way to relieve IBS mainly focus on dietary restriction, including low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) diet, low advanced glycation end products (AGEs) diet, gluten-free diet and low lactose diet, which can effectively improve abdominal discomfort symptoms of IBS patients. This article summarizes the research status quo of domestic and foreign scholars for IBS in recent years, including the pathophysiological mechanism of IBS, the relationship between dietary patterns and IBS intestinal flora, quantitative detection methods for FODMAPs components and AGEs in food. Food processing technologies are also introduced to reduce the content of FODMAPs and AGEs in food, in order to provide healthy and effective dietary intervention strategies for IBS patients.